1. Field of the Invention
The present invention relates to an image processing apparatus adapted to read information from an original having the information embedded therein and perform predetermined processing, a control method therefor, and a computer-readable storage medium storing a program for implementing the control method.
2. Description of the Related Art
Conventionally, there has been known a technique for controlling the operation of an image forming apparatus based on information contained in an original and information on the user of the image forming apparatus. For example, an image forming apparatus has been proposed in which identification information read from an original is sent to a server so as to acquire the attributes of the original, and the operation of the image forming apparatus is controlled based on the acquired attributes (see e.g. Japanese Patent Laid-Open Publication No. 2004-192610).
Further, a similar technique has been proposed in which when an image is read from an original, copying inhibition information is detected from the original, and an input operator code is checked to see if the operator is permitted to perform copying of the original, whereafter if the operator is permitted to perform copying of the original, copying is executed (see e.g. Japanese Patent Laid-Open Publication No. H07-115537).
In the above-mentioned prior art, however, even when a sheet original to be processed by the image forming apparatus has been modified from electronic data as the source of the sheet original, the image forming apparatus is permitted to carry out predetermined processing on the sheet original, which can cause a problem in some cases.
For example, assuming that a user authorized to print the sheet original but unauthorized to edit the same causes the image forming apparatus to scan the sheet original and perform the processing, it is necessary to change the processing depending on whether or not the sheet original has been edited.
Let it be assumed, by way of example, that a user A who printed form data passes the printed form data to a user B, and the user A is authorized to edit and print the form data while the user B is authorized to print the form data but unauthorized to edit the same. That is, the user B is not authorized to edit the form data, and hence the user B is not permitted to add or change numerals in the form data.
In such a case, however, the above-mentioned prior art allows the user B to print out a form, based on the printing rights granted to the user B, and then modify the printed form itself and generate a document file (electronic data) of the modified form using the image forming apparatus. This makes it possible to generate form data as if by editing the form data as the source of the printed form. For another example, a person unauthorized to approve purchase orders of articles can place a false stamp of approval on a purchase order and change the modified purchase order into electronic data using the image forming apparatus.
To prevent such forgery as mentioned above, it is necessary to determine not only whether or not a user is granted edit rights, but also whether or not a sheet original used by the user has been edited from a document file (electronic data) as the source of the sheet original. Therefore, the above-described prior art is incapable of solving the problem.